8.3.10.1 Extracting Members Split Between Volumes

If a member is split between several volumes of an old GNU format archive
most third party tar implementation will fail to extract
it. To extract it, use tarcat program (see section Concatenate Volumes into a Single Archive).
This program is available from
GNUtar home page. It concatenates several archive volumes into a single
valid archive. For example, if you have three volumes named from
`vol-1.tar' to `vol-3.tar', you can do the following to
extract them using a third-party tar:

$ tarcat vol-1.tar vol-2.tar vol-3.tar | tar xf -

You could use this approach for most (although not all) PAX
format archives as well. However, extracting split members from a PAX
archive is a much easier task, because PAX volumes are constructed in
such a way that each part of a split member is extracted to a
different file by tar implementations that are not aware of
GNU extensions. More specifically, the very first part retains its
original name, and all subsequent parts are named using the pattern:

%d/GNUFileParts.%p/%f.%n

where symbols preceeded by `%' are macro characters that
have the following meaning:

Meta-character

Replaced By

%d

The directory name of the file, equivalent to the
result of the dirname utility on its full name.

%f

The file name of the file, equivalent to the result
of the basename utility on its full name.

%p

The process ID of the tar process that
created the archive.

%n

Ordinal number of this particular part.

For example, if the file `var/longfile' was split during archive
creation between three volumes, and the creator tar process
had process ID`27962', then the member names will be:

When you extract your archive using a third-party tar, these
files will be created on your disk, and the only thing you will need
to do to restore your file in its original form is concatenate them in
the proper order, for example:

Ignore these warnings. The `PaxHeaders.*' directories created
will contain files with extended header keywords describing the
extracted files. You can delete them, unless they describe sparse
members. Read further to learn more about them.